7.5 Inclusions
Each size of inclusions shall not exceed 20% of the thickness of a thinner sheet or plate and 1.0mm maximum. Their number shall not exceed 4 in a bead length of 25mm.
7.6 Craters
A crater (a recess developed at a weld end) shall not exceed 20% of the thickness of a thinner sheet or plate. A crater in important portions shall not exceed the thickness
of a thinner sheet or plate.
7.7 Cracks
A weld shall be free from cracks that can be observed visually, by magnetic particle inspection, by color checking, etc. Provided that cranks not exceeding 10mm in length and 10mm in depth may be repaired.
H 7.8 Gap of the Base Metal
A gap of the base metal (C in Table 3 and Table 4), determined from the thickness of a thinner sheet or plate, shall be as described below.
(1) t < 2 mm: Max. 0.5 mm (2) 2 mm t < 3 mm: Max. 1.0 mm (3) t 3 mm: Max. 1.5 mm
If the required value is not satisfied by the dimensional tolerance of the base metal, discussions shall be held with the Quality Control Department and the affected Design Department.
H 7.9 Burn Through
(1) h shall be 0.5 mm or less.
(2) L is determined as follows. L is the total length for all portions. [1] t > 1 mm
(a) Welding of a pipe circumference: L shall be less than 40% of the circumference. (b) Straight bead welding: L shall be less than 25% of the total bead length.
[2] t 1 mm
L shall be less than 80% of the bead length for all beads.